i never ran it all the way in 4h either i thought it takes more power to drive the front and rear diffs so i disengage it also and yea i thought about it not being good at 109mph in 4h although ive never tried going that fast in 4h i havent done it so i really cant say

 

Why would YOU have to worry about that??

To the OP, I think you'd be better off to use the 32 spline output shaft in your 80E, and swap the input gear of your t-case. Much stronger than running the 27 spline stuff. At your weight & power level, snapping an output shaft (27 spline) can be a reality. I've done it.....

 

i do it that way because i figured it takes more power to drive two diff's so i do it just for traction on launch. ive never tried going all the way in 4h. doing over 100+mph in 4h sounds like opening a whole other can of worms. however ive never tried it so i cant really say, but im sure someone here has and maybe they will chime in on that subject.

 

I dont know, thats why i am asking. I do it all the time ( well at the track) . Heck evry 4x4 vehicle ive owned says dont go over 55 mph. Just wandered if we are hurting anything.

I agree swap the the Tcase input shaft.

 

I keep mine in 4HI for the full pass and put it back in 2HI in the shutdown area before making a turn onto the return road. I run drag radials on all 4 corners and make sure I keep constant tabs on tire roll out and check them after every dozen of passes or so to make sure the circumfrunces are the same. I spend alot of time mounting/remounting and rotating tires.

 

ok so we now know that a dodge is doing it all the way in 4h. any chey guys care to comment. also at 6800lbs my av weighs a little more. i also use 4 26" mt drag radials. not sure what the dodge has for a tranny and transfer case. another note the av has a rear coil suspension not leafs. i have upgraded with a complete hotkins trailing arms and sway bars. still would like to hear how some similar config chey guys r running

 

I run my truck all the way through in 4wd. I have been 116mph through the 1/4 so far and it felt ok. I'm in southern VA now and all I have is 1/8th mile. I went 95mph in the 1/8th the other night and it felt better not to have the other 1/8th mile to worry about in 4wd. LOL

Stock48 went 142mph in his truck in 4wd. I don't think I would have the ***** to do that.

 

Dodge's depending on year will use NP241/243 or NP271/273

 

I agree with both of these guys. Sharpshooter and I (lifted, procharged trucks) are in the process of going 80E right now. We just swapped both of the input shafts on our t-cases on friday. I think your t-case will be fine, your weak link is now the output shaft on your tranny.

 

My truck stays in 4hi for the entire pass. It won't shift out until I left.

Tim, I was just trying to give you a hard time buddy.